Short term results of anatomic stemless shoulder replacement with peripheral neck fixation.

Background: Most of the current stemless implants are using a central neck fixation design. Easytech Stemless replacements (FX Solutions®, Viriat, France) were developed promoting the idea of peripheral fixation of the stemless implant. The aim of this study was to analyze clinical and radiological results of this stemless TSA implanted for osteoarthritis (OA). Methods: A retrospective study of patients who received TSA with the Easytech® Anatomical Shoulder System (FX Solutions®, Viriat, France) for OA was completed at five clinical sites. Preoperative and minimum 2 year follow-up Constant Scores and X-rays were evaluated. Two independent orthopedic surgeons analyzed X-rays to assess anatomy reconstruction and component migration. Revisions and serious adverse effects were reviewed. Results: 129 patients were analyzed with an average follow-up of 37.47 months (24-54). Seven patients had a revision surgery and one of these resulted in the removal of the Anchor Base. The postoperative Constant Scores showed significant improvement with a mean raw Constant Score of 73.78 (38.0-100.0, mean increase 40.96, P < .0001) and mean adjusted Constant Score of 99.14 (42.20-133.30, mean increase 55.68, P < .0001). Radiographic review demonstrated that no modification of the center of rotation (COR) at minimum 24 months was greater than 3 mm and in comparison to preoperative radiographs, restoration of COR was lateralized in 25% of the cases, medialized in 61.5% and 13.5% had no change in COR. The mean value of the cervico-diaphyseal angle was 130.2° (114; 149) at 3 weeks and 129.9° (113.5; 144.0) at 2 years, demonstrating no significant difference (P = .16). 36 patients (35%) had calcar remodeling. Univariate and multivariate logistic regression found no significant factor, which was associated with the variation of the cervico-diaphyseal angle over time, center of rotation, calcar remodeling, or final Constant Score. The Walch B2 and C glenoid subset of patients (n = 13) had overall survival rate of 90.9% [95% CI 75.4-100.0] vs. 98.0% [95% CI 95.3-100.0] in other glenoid types (P < .01). Walch B2/C patients were 4.44 [95% CI 1.13, 17.6] times more likely to have a Constant Score <85 (P = .03). Conclusions: The peripheral fixation of the Easytech® Anatomical Shoulder System for OA provides excellent clinical results and imaging stability at minimum two year follow-up. Elderly age, gender and BMI do not affect the stability.

Two-year outcomes with a bioinductive collagen implant used in augmentation of arthroscopic repair of full-thickness rotator cuff tears: final results of a prospective multicenter study.

BACKGROUND: Full-thickness rotator cuff tears (FTRCTs) represent a common shoulder injury that, if untreated, can progress in size, become increasingly painful, and inhibit function. These lesions are often surgically repaired, with double-row arthroscopic repair often preferred for larger tears. Biological augmentation technologies have been developed to improve rates of postoperative radiographic retear and enhance patient-reported outcomes after surgical FTRCT repair. This study sought to confirm that augmented repair with a bioinductive bovine collagen implant results in favorable retear rates and patient outcomes with follow-up to 2 years. METHODS: A prospective multicenter cohort study was undertaken to determine the efficacy and safety of augmenting single- or double-row arthroscopic repair of FTRCTs with a bioinductive bovine collagen implant. Of 115 adult patients participating, 66 (57.4%) had medium (1-3-cm) tears and 49 (42.6%) had large (3-5-cm) tears. Magnetic resonance imaging and patient-reported outcomes (American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form [ASES] and Constant-Murley Score [CMS]) were performed and recorded at baseline, 3 months, 1 year, and 2 years. RESULTS: Mean duration of follow-up was 2.1 years (range, 1.5-2.9 years). Between baseline and 2-year follow-up, mean total thickness of the supraspinatus tendon increased by 12.5% for medium tears and by 17.1% for large tears. Radiographic retear was noted in 7 of 61 available patients (11.5%) with medium tears, and in 14 of 40 patients (35.0%) with large tears. In both groups, these tears primarily occurred before the 3-month follow-up visit (13 of 21 [61.9%]). Radiographic retear with the supplemented double-row (DR) repair technique was 13.2% overall (12 of 91 DR patients; 11.3% for medium tears and 15.8% for large tears). The minimal clinically important difference was achieved by >90% of patients with both medium and large tears for both ASES and CMS. There were 2 serious adverse events classified by the treating surgeon as being possibly related to the device and/or procedure (1 case of swelling/drainage and 1 case of intermittent pain). Nine patients (7.8%; 4 medium tears and 5 large tears) required reoperation of the index rotator cuff surgery. CONCLUSION: Final 2-year data from this study confirm that using this implant in augmentation of arthroscopic double-row repair of FTRCTs provides favorable rates of radiographic retear and substantial functional recovery. The relative safety of the device is also further supported.

Specific Design of a Press Fit Humeral Stem Provides low Stress Shielding in Reverse Shoulder Arthroplasty at minimum 5 Years FU.

Press fit fixation is becoming more popular in RSA to preserve, in theory, bone capital. Several studies report that bone resorption can be very high around humeral stems depending on their size, shape and mode of fixation. The aim of the current study is to mid-term follow-up clinical and radiological result of a press fit ovoid regular stem RSA in non acute trauma cases. Materials and Methods: We performed a retrospective monocentric study of patients continuously implanted with the Humeris® stem RSA for degenerative change of the shoulder. Nineteen shoulders, in eighteen patients (74.6 y.o (from 69 to 81)), were available at minimum five years follow-up. Results: The mean final adjusted Constant score was 111.9 (65 to 130), and the mean ASES score was 49.82 (10 to 60). Humeral resorption was observed in 21% of cases. We found a statistically significant (p = .014) lower adjusted Constant score in patients presenting with resorption on post-operative X-rays compared to those without resorption (115.6 vs. 98.25). Half cases of patients presenting a resorption underwent L'Episcopo procedure during surgery. Humeral resorption occurs the first year after surgery and do not increase even 8 years after surgery. Analysis demonstrated no correlation between the value of filling ratios and bone resorption. Conclusion: The current study confirms a low rate of stress shielding around the studied stem, with rare bony resorption and no osteopenia around the humeral stem. This study highlights the importance of choosing the appropriate proximal shape and length of the humeral stem for press fit fixation in RSA.

Retear rates and clinical outcomes at 1 year after repair of full-thickness rotator cuff tears augmented with a bioinductive collagen implant: a prospective multicenter study.

BACKGROUND: Biologic technologies can potentially augment existing arthroscopic rotator cuff repair to improve retear rates and postoperative outcomes. The purpose of this study was to evaluate healing rates and clinical outcomes of full-thickness rotator cuff repairs augmented with a bioinductive bovine collagen implant. METHODS: In this prospective multicenter study, investigators enrolled 115 patients (mean age, 60.4 years) with full-thickness rotator cuff tears. There were 66 (57.4%) medium (1-3 cm) tears and 49 (42.6%) large (3-5 cm) tears. Eligible patients consisted of those ≥21 years of age with chronic shoulder pain lasting longer than 3 months and unresponsive to conservative therapy. Patients underwent single- or double-row repair augmented with a bioinductive bovine collagen implant. At the baseline, 3 months, and 1 year, magnetic resonance imaging was performed and patients were assessed for American Shoulder and Elbow Surgeons (ASES) Shoulder Score and Constant-Murley Score (CMS). The primary failure end point was retear, classified as any new full-thickness defect observed on magnetic resonance imaging. RESULTS: There were 13 retears (11.3%) at 3 months, with an additional 6 (19 total [16.5%]) found at 1 year. In large tears, double-row repair had a significantly lower rate of retear at 3 months (P = .0004) and 1 year (P = .0001) compared with single-row repair. ASES and CMS scores significantly improved between the baseline and 1 year for medium and large tears. At 1 year, the minimally clinically important difference for ASES and CMS was met by 91.7% (95% CI: 84.9-96.1) and 86.4% (95% CI: 78.2-92.4) of patients, respectively. Patients without retear and those <65 years of age had significantly better CMS scores at 1 year when compared with those with retear and those ≥65 years (P < .05). There was no statistically significant difference in outcomes based on treatment of the biceps tendon. Of 9 reported reoperations in the operative shoulder, only 2 were considered potentially related to the collagen implant. CONCLUSION: Interim results from this prospective study indicate a favorable rate of retear relative to the literature and improvement in clinical function at 1 year after adjunctive treatment with the study implant augmenting standard arthroscopic repair techniques.

Redox Sensing within the Genus Shewanella.

A novel bacterial behavior called congregation was recently described in Shewanella oneidensis MR-1 as the accumulation of cells around insoluble electron acceptors (IEA). It is the result of a series of "run-and-reversal" events enabled by modulation of swimming speed and direction. The model proposed that the swimming cells constantly sense their surroundings with specialized outer membrane cytochromes capable of extracellular electron transport (EET). Up to this point, neither the congregation nor attachment behavior have been studied in any other strains. In this study, the wild type of S. oneidensis MR-1 and several deletion mutants as well as eight other Shewanella strains (Shewanella putrefaciens CN32, S. sp. ANA-3, S. sp. W3-18-1, Shewanella amazonensis SB2B, Shewanella loihica PV-4, Shewanella denitrificans OS217, Shewanella baltica OS155, and Shewanella frigidimarina NCIMB400) were screened for the ability to congregate. To monitor congregation and attachment, specialized cell-tracking techniques, as well as a novel cell accumulation after photo-bleaching (CAAP) confocal microscopy technique were utilized in this study. We found a strong correlation between the ability of strain MR-1 to accumulate on mineral surface and the presence of key EET genes such as mtrBC/omcA (SO_1778, SO_1776, and SO_1779) and gene coding for methyl-accepting protein (MCPs) with Ca+ channel chemotaxis receptor (Cache) domain (SO_2240). These EET and taxis genes were previously identified as essential for characteristic run and reversal swimming around IEA surfaces. CN32, ANA-3, and PV-4 congregated around both Fe(OH)3 and MnO2. Two other Shewanella spp. showed preferences for one oxide over the other: preferences that correlated with the metal content of the environments from which the strains were isolated: e.g., W3-18-1, which was isolated from an iron-rich habitat congregated and attached preferentially to Fe(OH)3, while SB2B, which was isolated from a MnO2-rich environment, preferred MnO2.

Failure analysis of rotator cuff repair: a comparison of three double-row techniques.

BACKGROUND: The use of suture anchors has made arthroscopic repair of the torn rotator cuff possible. However, objective evaluations have demonstrated high failure rates. The goal of this study was to compare the modes and rates of failure of two double-row arthroscopic repair techniques and the mini-open double-row technique. METHODS: Thirty pairs of fresh-frozen human shoulders were used in this study. The specimens were prepared to simulate a cuff defect, which was then repaired. The repairs were done with three different lateral row techniques (Mason-Allen sutures passed through transosseous tunnels, the knotless anchor method, and the corkscrew suture anchor method) with the same medial row technique (corkscrew suture anchors). Cyclic tests were conducted at 33 mm/s with a cyclic force of 10 to 180 N. Specimens were cycled to 5000 cycles or to failure as defined as formation of a 10-mm gap at the repair. Failure rates and failure modes of the suture, tendon, and bone-anchor interface were compared for the medial and lateral rows and among the three techniques. RESULTS: Fourteen of the twenty repairs made with the transosseous technique, fifteen of the twenty repairs made with the knotless anchor technique, and ten of the twenty repairs made with the corkscrew anchor technique survived 5000 cycles. The failure rates for the medial row were not significantly different among the three repair techniques. For the lateral row, there was a significant difference (p < 0.01) in the rate of failure among individual transosseous tunnel-suture complexes (32%), knotless anchor-suture complexes (48%), and corkscrew anchor-suture complexes (75%), with a similar suture-tendon failure rate for all three techniques. The tendon and repair complexes with corkscrew suture anchors had the smallest displacement both at the first and the 5000th cycle. CONCLUSIONS: Although repairs made with the anchor techniques had higher individual failure rates, the survival rates for the anchor techniques at the 5000th cycle were similar to that for the transosseous technique during cyclic tests. Suture failure was the main failure mode for the transosseous technique, whereas failure at the anchor-bone interface was the main failure mode for the anchor techniques.

Intramedullary nailing of humeral shaft fractures with a locking flexible nail.

BACKGROUND: Studies on intramedullary nailing of humeral shaft fractures in the orthopaedic literature have shown mixed results. The purpose of this investigation was to document the clinical outcome and complications associated with the use of a new flexible, locking intramedullary nail that can be implanted in the humerus in either a retrograde or an antegrade manner without violating the rotator cuff mechanism or damaging the articular surface of the humeral head. METHODS: Fifty consecutive patients with fifty-one humeral shaft fractures were entered into our prospective clinical outcome study. The fracture was classified on the basis of the anatomic location and pattern. Implant positioning and fracture alignment were assessed postoperatively. Complications were recorded, and the time to union was measured. Shoulder function was evaluated with use of a combination of the Constant shoulder score, Short Form-36 (SF-36) clinical outcome data, range-of-motion measurements, and a subjective pain-rating scale. RESULTS: Forty-one patients with forty-two fractures had an adequate duration of clinical follow-up (a mean of twenty-two months) for analysis. Thirty-nine fractures healed, with a mean time to clinical union of twelve weeks (range, four to fifty weeks). Thirty-eight of the forty-two shoulders had minimal or no pain. Thirty-six shoulders had a full range of motion. The mean Constant shoulder score was 90 points. Four patients had five complications, which included two nonunions, two hardware failures, and one wound infection. All four patients had been managed with a 7.5-mm nail. A multivariate analysis demonstrated that an age of more than fifty years was associated with a lower Constant score and that the occurrence of a complication was associated with a lower physical component score on the SF-36. CONCLUSIONS: The flexible humeral nail allows both retrograde and antegrade implantation and static locking. Nail insertion can be accomplished without violating the rotator cuff or damaging the articular surface of the humeral head. Although the nail functioned well in most of our patients, the use of a small-diameter (7.5-mm) nail was associated with a higher complication rate. This implant should be used with caution in any patient with a medullary canal diameter of